None of those regions represent an unified state of 1.4+ billion people. India's population is expected to hit 1.8+ billion before decreasing. Nothing else in the world comes close.
Predictions about what would've happened are always tricky, but I don't think you can ignore the fact that the US created the conditions for China's rise via Nixon's visit and Clinton's incorporation of China in the WTO. If neither of these acts had happened, and the US continued to maintain its embargo on China like it did in the first forty years of the PRC's existence, I don't think you can argue that China's catch up process would have been as fast.
Eventually, China would've still likely gotten there because a country of 1.4+ billion people was just too hard to ignore and even without Nixon's visit, Deng likely would've still attempted to pivot China into a market direction. But as we've seen with examples like Iran and North Korea, US sanctions especially during the height of its power could keep a country down for a long time. Simply put, if no Chinese students were allowed to study outside of China and China could not purchase any Western, Japanese, Korean, etc. technology, China would've had to reinvent much of this from scratch. That would've taken decades.
